[PyUP] Update feedgenerator to 2.2.0

[pyup-bot]

This PR updates feedgenerator from 2.0.0 to 2.2.0.

Changelog

2.2.0

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- Update to latest upstream code from Django 5.2
- Remove `pytz` as a dependency on non-Windows systems
- Use standardized `pyproject` file
- Drop support for EOL Python 3.7 & 3.8

2.1.0

------------------

* Modernize and improve tests ([32](https://github.com/getpelican/feedgenerator/pull/32) & [#34](https://github.com/getpelican/feedgenerator/pull/34) — thanks to venthur)
* Drop support for Python 3.6 and test on 3.10 & 3.11 ([35](https://github.com/getpelican/feedgenerator/pull/35) — thanks to hugovk)
* Exclude `tests_feedgenerator/__pycache__` from distribution ([33](https://github.com/getpelican/feedgenerator/pull/33) — thanks to BenSturmfels)

Links

• PyPI: https://pypi.org/project/feedgenerator
• Changelog: https://data.safetycli.com/changelogs/feedgenerator/

[pyup-bot]

Closing this in favor of #239